Motor torque control method, electronic equipment, storage medium and vehicle

Abstract

The invention discloses a motor torque control method, electronic equipment, a storage medium and a vehicle. The motor torque control method comprises the steps that it is determined that the vehicle is in a bumpy road condition; obtaining a wheel speed impact value according to the wheel speed of the vehicle; when the wheel speed impact value exceeds the impact value threshold value, the torque limiting torque of the motor is obtained according to the wheel speed impact value or the wheel speed impact value and the road slope; and controlling the range of the motor operation torque according to the motor torque limiting torque. According to the method, the range of the running torque of the motor can be controlled when the vehicle runs on different bumpy road conditions, hardware damage caused by the fact that a vehicle motor transmission system suffers from large impact torque is avoided, the dynamic property and safety of the vehicle are improved, and vehicle running safety accidents are avoided.

Description

Technical Field

[0001] The present invention relates to the field of vehicles, and in particular to a motor torque control method, an electronic device, a computer-readable storage medium and a vehicle. Background Art

[0002] New energy vehicles are different from fuel vehicles. Usually, new energy vehicles use a reducer with a fixed transmission ratio. The motor, reducer and wheels are directly connected in sequence. There is no clutch or other structure with vibration reduction and buffering between the drive shaft and the motor. The motor has the characteristics of constant torque at low speed and constant power at high speed, and the motor torque changes rapidly. When a new energy vehicle passes a bumpy road surface, such as a low hard obstacle or an unpredictable high road surface, the wheels will repeatedly "take off and touch the ground", which will cause the motor speed to change sharply and cause the hardware of the motor transmission system to be damaged by a relatively large impact torque. The motor torque needs to be limited. However, at the same time, on bumpy roads, especially in off-road conditions such as climbing, limiting the motor torque will cause the vehicle to lack power and slide down the slope, and the pitch angle is too large to cause rollover and other safety accidents. Not only will the passenger experience be poor, but even driving safety cannot be guaranteed.

[0003] The existing motor torque control method cannot accurately judge the bumpy road conditions of the vehicle, and cannot control the range of the motor operating torque according to the different states of the bumpy road conditions when the vehicle is driving on bumpy roads, resulting in the vehicle's motor transmission system being subjected to a large impact torque, and the vehicle's dynamics and safety are low. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present invention is to provide a motor torque control method, which can control the range of motor operating torque when driving on different bumpy roads, avoid hardware damage caused by large impact torque on the vehicle motor transmission system, improve vehicle power and safety, and avoid the occurrence of vehicle driving safety accidents.

[0005] The second objective of the present invention is to provide an electronic device.

[0006] A third object of the present invention is to provide a computer-readable storage medium.

[0007] A fourth object of the present invention is to provide a vehicle.

[0008] In order to solve the above problems, an embodiment of the first aspect of the present invention provides a motor torque control method, including: determining that a vehicle is in a bumpy road condition; obtaining a wheel speed impact value according to the wheel speed of the vehicle; when the wheel speed impact value exceeds an impact value threshold, obtaining a motor torque limit according to the wheel speed impact value or the wheel speed impact value and the road slope; and controlling the range of the motor operating torque according to the motor torque limit.

[0009] According to the motor torque control method of the embodiment of the present invention, it is determined whether the vehicle is traveling on a bumpy road condition. When the vehicle is traveling on a bumpy road condition, the wheel speed impact value is obtained. If the wheel speed impact value exceeds the impact value threshold, the motor limit torque is obtained through the wheel speed impact value or the wheel speed impact value and the road slope. The range of the motor operating torque is controlled according to the motor limit torque to avoid hardware damage caused by a large impact torque to the vehicle motor transmission system, thereby improving the vehicle's power and safety and avoiding the occurrence of vehicle driving safety accidents.

[0010] In some embodiments, the motor torque limit is obtained according to the wheel speed impact value and the road slope, including: when the road slope is less than a slope threshold, obtaining a motor torque limit coefficient according to the wheel speed impact value; obtaining a first motor torque limit according to the motor torque limit coefficient and the maximum allowable torque of the motor, and using the first motor torque limit as the motor torque limit to control the range of the motor operating torque.

[0011] In some embodiments, the motor torque limit is obtained according to the wheel speed impact value and the road slope, including: when the road slope is greater than or equal to a slope threshold, obtaining a motor torque limit coefficient according to the wheel speed impact value, and obtaining a vehicle climbing torque lower limit according to vehicle information and the road slope; obtaining a first motor torque limit according to the motor torque limit coefficient and the maximum allowable torque of the motor, obtaining a second motor torque limit according to the first motor torque limit and the vehicle climbing torque lower limit, and using the second motor torque limit as the motor torque limit to control the range of the motor operating torque.

[0012] In some embodiments, the vehicle climbing torque limit is obtained according to the vehicle information and the road slope, including: obtaining the vehicle climbing torque lower limit according to the road slope, the vehicle pitch angle, the vehicle speed and the vehicle weight.

[0013] In some embodiments, obtaining the motor torque limit coefficient according to the wheel speed impact value includes: searching for a calibration mapping relationship according to the wheel speed impact value to obtain the motor torque limit coefficient, wherein the calibration mapping relationship is a correspondence between the wheel speed impact value and the motor torque limit coefficient, and the wheel speed impact value is inversely correlated with the motor torque limit torque.

[0014] In some embodiments, controlling the range of the motor operating torque according to the motor torque limit includes: controlling the motor operating torque output at a preset motor torque change rate so that the motor operating torque is within the torque range defined by the motor torque limit.

[0015] In some embodiments, obtaining a wheel speed impact value based on the wheel speed of the vehicle includes: obtaining the wheel speed of the vehicle within a preset time period; obtaining a fitting equation of wheel speed and time; obtaining an estimated wheel speed value based on the fitting equation; and obtaining a wheel speed difference based on the estimated wheel speed value and the corresponding measured wheel speed value as the wheel speed impact value.

[0016] In some embodiments, determining that a vehicle is in a bumpy road condition includes: when the vertical acceleration of the vehicle in a direction perpendicular to the vehicle exceeds a vertical acceleration threshold and the number of times the vertical acceleration exceeds the vertical acceleration threshold reaches a number threshold, determining that the vehicle is traveling on the bumpy road condition, wherein the number threshold is ≥1.

[0017] In some embodiments, the motor torque control method further includes: when the wheel speed impact value is less than the impact value threshold and the duration of the wheel speed impact value being less than the impact value threshold reaches a time threshold, exiting the torque limiting control of the motor of the vehicle, and the time threshold is ≥0.

[0018] A second aspect of the present invention provides an electronic device, comprising: at least one processor; a memory communicatively connected to the at least one processor; the memory storing a computer program executable by the at least one processor, wherein the at least one processor implements the motor torque control method described in the above embodiment when executing the computer program.

[0019] According to the electronic device of the embodiment of the present invention, the corresponding motor torque control program can be stored in the memory. When implementing the charging control method, the processor runs the program in the memory to determine whether the vehicle is traveling on a bumpy road condition. When the vehicle is traveling on different bumpy roads, the range of the motor operating torque is controlled according to the motor torque limit torque, thereby preventing the vehicle motor transmission system from being subjected to a large impact torque and causing hardware damage, thereby improving the vehicle's power and safety, and avoiding the occurrence of vehicle driving safety accidents.

[0020] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the motor torque control method described in the above embodiment when executed.

[0021] A fourth aspect of the present invention provides a vehicle, comprising: a motor; a plurality of sensors for detecting vehicle information and road surface information; and a controller, wherein the controller is connected to the plurality of sensors and the motor, and is used to control the motor according to the motor torque control method described in the above embodiment.

[0022] In a vehicle according to an embodiment of the present invention, multiple sensors detect vehicle information and road surface information in real time to determine whether the vehicle is traveling on bumpy roads. When the vehicle is traveling on different bumpy roads, a controller controls the range of the motor's operating torque according to the motor's torque limit torque to prevent the vehicle's motor transmission system from being subjected to large impact torque and causing hardware damage, thereby improving the vehicle's power and safety and avoiding the occurrence of vehicle driving safety accidents.

[0023] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 is a flow chart of a motor torque control method according to an embodiment of the present invention; Figure 2 is a flow chart of the overall logic of motor torque control according to one embodiment of the present invention; Figure 3 is a flowchart of the steps of obtaining a module according to one embodiment of the present invention; Figure 4 is a flow chart of the steps of a calculation module according to one embodiment of the present invention; Figure 5 is a schematic diagram of a fitted wheel speed-time curve according to an embodiment of the present invention; Figure 6 is a flow chart of control module steps according to one embodiment of the present invention; Figure 7 is a structural block diagram of an electronic device according to an embodiment of the present invention; Figure 8 is a structural block diagram of a vehicle according to an embodiment of the present invention.

[0025] Reference numerals: Electronic device 100; vehicle 200; Processor 101 ; memory 102 ; motor 201 ; sensor 202 ; controller 203 . DETAILED DESCRIPTION

[0026] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0027] The first aspect of the present invention provides a motor torque control method, which can control the range of the motor operating torque when driving on different bumpy road conditions, avoid hardware damage caused by large impact torque on the vehicle's motor transmission system, improve vehicle power and safety, and avoid the occurrence of vehicle driving safety accidents.

[0028] Reference below Figure 1 A motor torque control method according to an embodiment of the first aspect of the present invention is described. Figure 1 As shown, the method at least includes steps S1 to S4.

[0029] Step S1, determining that the vehicle is in a bumpy road condition.

[0030] Specifically, when the vehicle is on a bumpy road, it may pass through low hard obstacles and unexpected high bumps on the road, and the wheels will repeatedly "take off and touch the ground". When in the air, the motor speed changes sharply, causing the motor transmission system hardware to be subjected to a relatively large impact torque, resulting in hardware damage. Therefore, the motor torque needs to be limited.

[0031] The acceleration sensor built into the vehicle can detect the acceleration changes of the vehicle in different directions. Under bumpy road conditions, the vertical acceleration (i.e. up and down vibration) of the vehicle will change significantly. By analyzing these acceleration data, it can be determined whether the vehicle is in bumpy road conditions.

[0032] Step S2, obtaining a wheel speed impact value according to the wheel speed of the vehicle.

[0033] Specifically, if it is determined through multiple sensors that the vehicle is in a bumpy road condition, the wheel speed impact value is obtained based on the wheel speed of the vehicle. The wheel speed impact value is an indicator used to evaluate the degree of impact on the wheels of the vehicle during driving, and is usually closely related to factors such as wheel acceleration, speed change rate and road conditions. When the wheel speed impact value is too large, it may cause damage to the hardware of the motor transmission system. At this time, it is necessary to limit the motor torque, reduce the wheel speed impact value, protect vehicle components, and ensure safe driving of the vehicle.

[0034] When obtaining the wheel speed impact value, it is necessary to obtain the vehicle's wheel speed data through a wheel speed sensor. The wheel speed sensor is usually installed on the wheel and can measure the wheel rotation speed in real time and convert the data into an electrical signal for transmission. After obtaining the wheel speed data, the data needs to be processed to calculate the wheel speed acceleration. After obtaining accurate wheel speed acceleration data, the wheel speed impact value is further calculated. The wheel speed impact value is usually related to factors such as the rate of change of the wheel speed acceleration and the mass of the vehicle.

[0035] Step S3, when the wheel speed impact value exceeds the impact value threshold, obtaining the motor torque limit according to the wheel speed impact value or the wheel speed impact value and the road slope.

[0036] Specifically, when the wheel speed impact value of the vehicle exceeds the preset impact value threshold, the vehicle is in an airborne state, and the motor transmission system hardware is subjected to a relatively large impact torque. In order to protect the vehicle's transmission system and motor from damage, when the wheel speed impact value exceeds the threshold, the available range of the motor operating torque that ensures the safe driving of components and the entire vehicle is obtained based on information such as the impact value and the road slope.

[0037] The present invention controls the motor torque under different states of bumpy roads. If the vehicle is on a horizontal bumpy road, the motor limiting torque is obtained according to the wheel speed impact value (the motor torque is controlled by the motor available torque); if the vehicle is on a bumpy road while climbing a slope, the motor limiting torque is obtained according to the wheel speed impact value and the road slope (the motor torque is controlled by the motor available torque and the minimum torque for suppressing the vehicle from sliding down the slope and flipping). In both states, the motor torque control is exited when the wheel speed impact value is less than the set impact value threshold.

[0038] The motor torque limit is calculated based on the wheel speed impact value and the road slope. The purpose is to minimize the impact on the transmission system components while ensuring that the vehicle can drive safely and stably. The wheel speed impact value reflects the degree of impact on the current vehicle. The higher the wheel speed impact value, the greater the torque limit is required to reduce potential damage; on steep uphill or downhill sections, the vehicle needs more torque to maintain stable driving. Therefore, under the premise of ensuring that the vehicle can drive normally on the current road slope, the motor torque limit is calculated to reduce the load on the transmission system and motor, thereby reducing the risk of hardware damage, while ensuring that the vehicle can drive safely and stably on the current road slope.

[0039] Step S4, controlling the range of the motor operating torque according to the motor torque limit.

[0040] Specifically, when it is determined that the vehicle is in a bumpy road condition, the wheel speed impact value is obtained in real time. When the wheel speed impact value exceeds the impact value threshold, the motor limit torque is calculated based on the wheel speed impact value and the road slope. The motor limit torque = motor peak torque × torque limit coefficient. The motor limit torque is not necessarily less than the current motor operating torque. If the motor limit torque is greater than the current motor operating torque, it operates at the current motor operating torque. If the motor limit torque is less than the current motor operating torque, the current motor operating torque is reduced. The motor torque output is controlled to be within the range of the motor operating torque based on the motor torque change rate calibrated by the actual vehicle, thereby controlling the torque output of the motor to ensure that the vehicle is driven under safe and stable conditions.

[0041] According to the motor torque control method of the embodiment of the present invention, it is determined whether the vehicle is traveling on a bumpy road condition. When the vehicle is traveling on a bumpy road condition, the wheel speed impact value is obtained. If the wheel speed impact value exceeds the impact value threshold, the motor limit torque is obtained through the wheel speed impact value or the wheel speed impact value and the road slope. The range of the motor operating torque is controlled according to the motor limit torque to avoid hardware damage caused by a large impact torque to the vehicle motor transmission system, thereby improving the vehicle's power and safety and avoiding the occurrence of vehicle driving safety accidents.

[0042] For example, the motor torque control method on bumpy roads realizes the hardware protection of components and the safe driving of the whole vehicle, which is the difficulty and key point of new energy vehicles, and is related to the vehicle's power, safety, off-road capability and safety. When the vehicle is driving on bumpy roads such as off-road roads and climbing, the wheels will repeatedly take off and touch the ground, causing a large impact torque on the various components of the transmission system. Therefore, there is a limited torque demand for the motor torque, and at the same time, it is necessary to consider the vehicle's safety accidents such as sliding down the slope and flipping caused by insufficient power due to the reduction of the available torque of the motor. Therefore, the motor torque control method of new energy vehicles established by the present invention realizes the torque control of the motor through three modules: acquisition module, calculation module and control module. First, the vehicle's operating state parameters (including road slope, vehicle pitch angle, vehicle speed, wheel speed and vertical acceleration, etc.) are obtained through various sensors on the vehicle, and the vehicle's vertical acceleration is used to determine whether the vehicle has entered a bumpy road surface; then, after it is determined that it has entered a bumpy road surface, the calculation module calculates the wheel speed impact value according to the change in the vehicle's wheel speed, which is used to determine whether the wheel is in the air; finally, after it is determined that the wheel is in the air state, the transmission system component hardware and the safe driving of the whole vehicle are comprehensively considered, and the motor torque is controlled according to the preset motor torque change rate (actual vehicle calibration). The preset values ​​and judgment thresholds of various parameters of the technology of the present invention can be adjusted, and its logic method can be applied to different new energy vehicle models. The main purpose of the present invention is to use the vehicle's sensors and controllers to achieve the problem of safe driving of new energy vehicles on bumpy roads, including but not limited to: motor torque control system logic, bumpy road judgment, vehicle air and ground judgment strategy, and motor torque control method that comprehensively considers the normal operation of component hardware and safe driving of the whole vehicle.

[0043] Reference below Figure 2 The steps of the overall logic flow chart of the present invention are illustrated by way of example, and the specific contents are as follows: Step S5, start.

[0044] Step S6, acquisition module: acquires vehicle operating parameter information, including: road slope, vehicle pitch angle, wheel speed, longitudinal and vertical acceleration, etc.

[0045] Step S7, calculation module: taking the difference between the simulated and measured wheel speeds as the wheel speed impact value, as a basis for determining whether the wheel is airborne or touching the ground.

[0046] Step S8, control module: comprehensively consider the hardware of the transmission system components and the driving safety of the whole vehicle, and control the motor torque output according to the motor torque change rate calibrated by the actual vehicle.

[0047] Step S9, end.

[0048] In some embodiments, the motor torque limit is obtained according to the wheel speed impact value and the road slope, including: when the road slope is less than a slope threshold, obtaining the motor torque limit coefficient according to the wheel speed impact value; obtaining the first motor torque limit according to the motor torque limit coefficient and the maximum allowable torque of the motor, and using the first motor torque limit as the motor torque limit to control the range of the motor operating torque.

[0049] Specifically, if the slope value is not considered and the motor is torque-limited at any slope, the vehicle may slip, flip, and other accidents due to insufficient power. Therefore, when the road slope is less than the slope threshold, the motor torque limit coefficient is obtained according to the wheel speed impact value. At this time, the vehicle is on a bumpy road section, but there is no slope or the slope is relatively small; the determination of the motor torque limit coefficient needs to be based on the actual vehicle bumpy road calibration test, and the impact torque of the easily damaged parts (such as the differential) of the simulated transmission system is made smaller than the yield torque. After obtaining the motor torque limit coefficient, the first motor torque limit is obtained according to the motor torque limit coefficient and the maximum allowable torque of the motor. The first motor torque limit is used as the motor torque limit to control the range of the motor operating torque. The first motor torque limit can be understood as the motor torque limit when the vehicle is not climbing a bumpy road. At this time, the motor operating torque cannot exceed the first motor torque limit.

[0050] In some embodiments, a motor torque limit is obtained based on a wheel speed impact value and a road slope, including: when a road slope is greater than or equal to a slope threshold, a motor torque limit coefficient is obtained based on the wheel speed impact value, and a vehicle climbing torque lower limit is obtained based on vehicle information and the road slope; a first motor torque limit is obtained based on the motor torque limit coefficient and a maximum allowable torque of the motor, a second motor torque limit is obtained based on the first motor torque limit and a vehicle climbing torque lower limit, and the second motor torque limit is used as the motor torque limit to control the range of the motor operating torque.

[0051] Specifically, when the road slope is greater than or equal to the slope threshold, the vehicle is on a bumpy road and in a climbing state. At this time, the slope is large and it is necessary to avoid the torque limit being too small to cause the vehicle to slide or flip; the motor torque limit coefficient is obtained according to the wheel speed impact value, and the vehicle climbing torque lower limit is obtained according to the vehicle information and the road slope. The vehicle information may include: vehicle type, motor performance, vehicle weight and transmission system efficiency; the road slope is an important factor affecting the vehicle's climbing ability and needs to be accurately measured and obtained. The road slope is usually expressed in percentage or angle. After obtaining the vehicle information and road slope, the climbing torque lower limit is calculated. value, and then obtain the first motor torque limit torque through the motor torque limit coefficient and the maximum allowable torque of the motor, and then obtain the second motor torque limit torque according to the first motor torque limit torque and the vehicle climbing torque lower limit value. The second motor torque limit torque can be understood as the motor torque limit when the vehicle climbs a bumpy road. The second motor torque limit torque is used as the motor torque limit torque, and the range of the motor operating torque is controlled according to the motor torque limit torque. The second motor torque limit torque is greater than the vehicle climbing torque lower limit value. At this time, the vehicle motor output torque is between the vehicle climbing torque lower limit value and the second motor torque limit torque to ensure safe driving of the vehicle at the current slope.

[0052] In some embodiments, the vehicle climbing torque limit is obtained according to vehicle information and road slope, including: obtaining the vehicle climbing torque lower limit according to road slope, vehicle pitch angle, vehicle speed and vehicle weight.

[0053] Specifically, the greater the road slope, the greater the gravity component that the vehicle needs to overcome when climbing, so the greater the torque required; the vehicle pitch angle reflects the degree of inclination of the vehicle body during the climbing process. The change in pitch angle will affect the distribution of the vehicle's center of gravity and the contact between the tire and the ground, thereby affecting the demand for climbing torque; the vehicle speed is constant, and the faster the vehicle speed, the smaller the required traction (according to P=FV, when the power P is constant and the speed V increases, the traction F decreases), but in the process of climbing, in order to maintain sufficient traction to overcome the gravity component, the vehicle usually needs to reduce the speed; the greater the vehicle weight, the greater the gravity that needs to be overcome when climbing, so the required torque also increases accordingly. Considering the influence of road slope, vehicle pitch angle, vehicle speed and vehicle weight on the lower limit of vehicle climbing torque, an accurate lower limit of climbing torque is obtained.

[0054] Reference below Figure 3 The steps of obtaining the module are illustrated by examples, and the specific contents are as follows: Step S10, obtaining the vertical acceleration of the vehicle.

[0055] Step S11, determine whether it is greater than a threshold, if so, execute step S12, otherwise, execute step S10.

[0056] Step S12, entering a bumpy road.

[0057] Step S13, obtaining vehicle operating status parameters.

[0058] For example, the acquisition module obtains the vehicle's road condition information and operating status parameters through the vehicle sensor, such as Figure 3 As shown, it mainly includes parameters such as the slope of the road surface, the pitch angle, the steering angle, the vertical acceleration, the longitudinal acceleration, the depth of the accelerator pedal and the wheel speed. When the magnitude of the vertical acceleration obtained by the acceleration sensor of the whole vehicle exceeds a certain threshold, it is determined that the vehicle has vibrated in the vertical direction, and from the result, it is judged that the vehicle is traveling on a bumpy road. In actual motor control, it is considered to exceed the threshold twice or three times to avoid misjudgment of general road conditions such as puddles, sudden obstacles and manhole covers. After identifying the bumpy road surface, the motor control method implementation process of the present invention is entered, and the vehicle operation status parameters are passed to the calculation module to realize the calculation of the vehicle impact value, and the control module realizes the control of the motor torque.

[0059] In some embodiments, obtaining the motor torque limit coefficient according to the wheel speed impact value includes: searching for a calibration mapping relationship according to the wheel speed impact value to obtain the motor torque limit coefficient, wherein the calibration mapping relationship is a correspondence between the wheel speed impact value and the motor torque limit coefficient, and the wheel speed impact value is inversely correlated with the motor torque limit torque.

[0060] Specifically, the wheel speed impact value usually refers to the value of the instantaneous change in wheel speed during vehicle driving. This wheel speed impact value reflects the magnitude of the impact force or disturbance on the wheel; the motor torque is a measure of the motor output force, which determines the vehicle's ability to accelerate, climb or overcome resistance. During vehicle driving, the motor torque needs to be adjusted according to actual conditions to ensure the vehicle's power performance and stability. The calibration mapping relationship refers to establishing a corresponding relationship between the wheel speed impact value and the motor torque limit coefficient. The calibration mapping relationship is obtained through actual vehicle calibration based on the impact torque of the components being less than the yield torque, and the calibration mapping relationship is stored in the vehicle's control system. During the calibration process, it is necessary to measure the torque output of the motor under different wheel speed impact values ​​and record the corresponding data. Then, these data are used to establish a mapping relationship between the wheel speed impact value and the motor torque limit coefficient. After establishing the calibration mapping relationship, the corresponding motor torque limit coefficient can be found according to the actual wheel speed impact value. When the wheel speed impact value increases, the impact force or disturbance on the wheel increases. In order to maintain the stability of the vehicle, it is necessary to reduce the torque output of the motor, that is, reduce the motor torque limit coefficient. Therefore, the wheel speed impact value is inversely correlated with the motor limit torque.

[0061] In some embodiments, controlling the range of the motor operating torque according to the motor torque limit includes: controlling the motor operating torque output at a preset motor torque change rate so that the motor operating torque is within the torque range limited by the motor torque limit.

[0062] Specifically, the motor torque change rate should comprehensively consider the torque change effect and whether the passengers feel obvious vibration (adjusted and calibrated according to the actual vehicle speed and motor parameters) to determine the motor available torque change rate to reduce the frustration of torque change. The preset motor torque change rate refers to the rate of change of torque over time when the motor operating torque is reduced. This change rate is set based on factors such as the vehicle's power performance, stability requirements, and the driver's comfort needs. It ensures that the torque reduction is smooth and controllable, and avoids discomfort or damage to the vehicle and passengers caused by sudden torque changes. When it is necessary to reduce the motor operating torque (for example, when the wheel speed impact value is detected to increase), the controller will gradually reduce the motor's torque output according to the preset motor torque change rate. This process is continuous, and the motor torque change rate is a determined value calibrated according to the actual vehicle, that is, the motor torque change slope is a fixed value.

[0063] During the torque reduction process, the controller will continuously monitor the actual torque output of the motor and compare it with the motor limit torque. When the actual torque output of the motor is within the torque range specified by the motor limit torque, the controller will stop further torque reduction operations to ensure that the motor operates within a safe torque range.

[0064] In some embodiments, a wheel speed impact value is obtained based on the wheel speed of the vehicle, including: obtaining the wheel speed of the vehicle within a preset time period; obtaining a fitting equation of the wheel speed and time; obtaining an estimated wheel speed value based on the fitting equation; and obtaining a wheel speed difference based on the estimated wheel speed value and the corresponding measured wheel speed value as the wheel speed impact value.

[0065] Specifically, when obtaining the wheel speed impact value according to the wheel speed of the vehicle, the wheel speed data within a preset time period is first collected from the wheel speed sensor of the vehicle; then the collected wheel speed data is fitted to obtain a fitting equation that describes the change of wheel speed over time. After obtaining the fitting equation of wheel speed and time, the fitting equation of wheel speed and time can be used to estimate the estimated wheel speed at any time point, and the wheel speed difference is obtained according to the estimated wheel speed and the corresponding measured wheel speed value. The wheel speed difference reflects the fluctuation or change of the wheel speed within the preset time period. The calculated wheel speed difference is used as the wheel speed impact value to evaluate the magnitude of the impact or disturbance to the vehicle within the preset time period.

[0066] Reference below Figure 4 The calculation module steps are illustrated by examples, the specific contents are as follows: Step S14, preset time period.

[0067] Step S15, preset wheel speed sampling frequency.

[0068] Step S16, fitting the wheel speed equation.

[0069] Step S17, estimating the current wheel speed.

[0070] Step S18, wheel speed sensor.

[0071] Step S19, measuring the current wheel speed.

[0072] Step S20: wheel speed impact value.

[0073] For example, when the wheel is lifted off the ground, the motor resistance is temporarily lost, idling occurs, and the motor speed increases rapidly; when the wheel touches the ground, the wheel speed suddenly drops, the motor resistance is instantly restored, and the motor speed drops rapidly again. Therefore, the state of the wheel lifting off and touching the ground can be determined by the wheel impact value of the wheel lifting off and touching the ground on a bumpy road. The wheel speed impact value calculation method is as follows Figure 4 As shown. Multiple wheel speeds are obtained at a preset frequency within a preset time period, fitted into a wheel speed equation, the current wheel speed is estimated, and the difference between the current wheel speed measured by the wheel speed sensor is calculated, and this difference is used as the impact value received by the vehicle during driving.

[0074] For example, when the vehicle is accelerating, a certain measured wheel speed is shown in Table 1 below: Table 1 Wheel speed and time comparison table

[0075] The fitted wheel speed-time curve is approximately a straight line, such as Figure 5 shown.

[0076] The same treatment can be applied to other vehicles during driving, except that the wheel speed-time equation is different. The wheel speed simulation value at the next moment can be determined based on the wheel speed-time formula when the vehicle is driving normally. When the difference between the calculated wheel speed value and the measured value is too large, the motor torque control process of the present invention is entered based on the wheel speed impact value.

[0077] In some embodiments, determining that the vehicle is in a bumpy road condition includes: when the vertical acceleration of the vehicle in a direction perpendicular to the vehicle exceeds a vertical acceleration threshold and the number of times the vertical acceleration exceeds the vertical acceleration threshold reaches a number threshold, determining that the vehicle is traveling on a bumpy road condition, wherein the number threshold is ≥1.

[0078] Specifically, a vertical acceleration threshold is set to determine whether the vertical acceleration of the vehicle exceeds the range of normal driving, so as to preliminarily determine whether the vehicle is traveling on bumpy road conditions. The vertical acceleration of the vehicle in a direction perpendicular to the vehicle is monitored in real time through an acceleration sensor installed on the vehicle. The vertical acceleration monitored in real time is compared with the set threshold. If the vertical acceleration exceeds the threshold, it is recorded. In addition to the vertical acceleration threshold, a number threshold needs to be set. The number threshold is used to determine whether the number of times the vertical acceleration exceeds the threshold within a period of time reaches the number threshold; the number threshold can be set to ≥1, that is, as long as the vertical acceleration threshold is exceeded once, it can be considered that the vehicle is traveling on a bumpy road condition. A higher number threshold can also be set according to actual needs. When the number of times the vertical acceleration is monitored to exceed the vertical acceleration threshold reaches or exceeds the set number threshold, it can be determined that the vehicle is traveling on a bumpy road condition.

[0079] In some embodiments, the motor torque control method further includes: when the wheel speed impact value is less than the impact value threshold and the duration of the wheel speed impact value being less than the impact value threshold reaches a time threshold, exiting the torque limiting control of the vehicle's motor, and the time threshold is ≥0.

[0080] Specifically, the wheel speed impact value is obtained according to the wheel speed of the vehicle. When the wheel speed impact value is less than the impact value threshold, the wheel is not in an airborne state, and the small wheel speed impact value will not cause impact damage to the hardware. When the wheel speed impact value is less than the impact value threshold and the duration reaches the time threshold, the time threshold can be set to ≥0. The time threshold will be set to a value greater than 0, at which time the torque limiting control of the vehicle's motor is exited.

[0081] For example, due to the complexity of the actual driving surface of the vehicle, the motor torque control system may misjudge and call the motor torque limit program when torque limit is not needed, affecting the vehicle's power and driving experience. The current general motor torque control method is based on the normal operation of the hardware of the transmission system components (such as the yield torque of the differential) to calibrate the parameters of the motor's available torque, but does not consider the safety issues of the whole vehicle such as sliding down the slope and flipping due to insufficient power when the vehicle climbs on bumpy roads. The existing motor torque control method has the disadvantages of sudden changes in motor torque and long reaction time. The sudden change in torque will cause body shaking and setbacks, affecting the riding experience.

[0082] In view of the shortcomings of the above existing motor torque control methods, the present invention comprehensively considers the motor torque requirements for vehicle driving safety and normal operation of component hardware when the vehicle is driving on bumpy roads, can quickly reduce and limit the torque, protect the hardware of the drive and transmission system (such as differentials, etc.), avoid impact damage, and at the same time consider the vehicle's safety driving problems such as sliding and flipping when climbing. The motor torque control system of the present invention adopts a gradual change method when limiting the motor torque, which can reduce the frustration of sudden torque changes and increase the comfort of riding in the vehicle. At the same time, the present invention does not require the addition of additional hardware equipment, which can reduce the cost of vehicle development and improve the progress of vehicle development.

[0083] The specific process of the motor torque control method of the present invention should be: first, determine whether the vehicle is on a bumpy road surface based on the vertical acceleration; then, determine whether the vehicle is on a bumpy road surface based on the slope; then, determine whether to enter the motor torque control based on the wheel speed impact value; finally, perform different controls on the motor torque under different bumpy road surfaces. On a horizontal bumpy road surface, when the wheel speed impact value is greater than a threshold, the motor torque is controlled by the motor available torque; when climbing a bumpy road surface, when the wheel speed impact value is greater than a threshold, the larger value of the motor available torque and the minimum torque that suppresses the vehicle from sliding down the slope and flipping is used as the torque to control the motor; when the wheel speed impact value is less than the threshold, exit the motor torque control.

[0084] Reference below Figure 6 The control module steps are illustrated with examples, the specific contents are as follows: Step S21, obtaining the wheel speed impact value.

[0085] Step S22, determine whether it is greater than a preset threshold, if so, execute step S23, otherwise, execute step S21.

[0086] Step S23: motor torque control.

[0087] Step S24, determining whether the slope is greater than a preset threshold, if so, executing step S28, otherwise, executing step S25.

[0088] Step S25, generally bumpy road surface.

[0089] Step S26: The component hardware operates normally.

[0090] Step S27, reducing the available torque of the motor.

[0091] Step S28, vehicle climbing state.

[0092] Step S29, comprehensively consider the driving safety of the whole vehicle and the normal operation of the hardware components.

[0093] Step S30, reducing the available torque of the motor.

[0094] Step S31, minimum torque to suppress the vehicle from rolling down the slope and turning over.

[0095] Step S32, output a larger value.

[0096] Step S33, presetting the motor torque change rate.

[0097] Step S34, controlling the motor torque output.

[0098] Step S35, wheel speed impact value determination.

[0099] Step S36, touching the ground.

[0100] Step S37, exit the motor torque limiting system.

[0101] For example, when a vehicle is driving on a bumpy road, in order to prevent the vehicle drive system from being subjected to a relatively large impact torque and causing hardware damage (such as the differential), when the wheel speed impact value is greater than the preset threshold, the vehicle is judged to be in an air-free state and enters the motor torque control system: when the wheel is in the air, the motor controller limits the motor torque: the motor available torque = the motor peak torque × the torque limit coefficient; when the wheel touches the ground, the motor available torque is restored to the motor peak torque, and the motor torque control system is exited. Among them, the motor torque control needs to determine two parameters: the torque limit coefficient and the motor torque change rate, both of which need to be determined based on the actual vehicle calibration. The determination of the motor torque limit coefficient needs to be based on the actual vehicle bumpy road calibration test, according to the impact torque of the easily damaged parts of the simulated transmission system (such as the differential), so that the impact torque is less than the yield torque. The motor torque change rate should comprehensively consider the torque change effect and whether the passengers feel obvious vibration (adjusted and calibrated according to the actual vehicle speed and motor parameters) to determine the motor available torque change rate to reduce the frustration of torque change. However, when the vehicle is climbing a slope, especially in climbing conditions under harsh road conditions such as off-road driving, limiting the motor output torque will cause the vehicle to slide down the slope due to insufficient power, and roll over due to excessive pitch angle. Therefore, when such extreme working conditions occur, the plastic deformation of components caused by wheel speed impact must be temporarily ignored, and the safe driving of the entire vehicle must be ensured first: determine the minimum torque to suppress the vehicle from sliding down the slope or rolling over based on the road slope, vehicle pitch angle, vehicle speed and vehicle weight.

[0102] For example, in theory, when a vehicle is climbing a slope, it is subject to gravity mg (vertically downward), support force F (vertically upward on the slope), traction force F (upward on the slope), and friction force f (downward on the slope). If the speed of the vehicle is V, the output power of the motor is: Pout = F×V. If the vehicle is to be prevented from sliding down the slope, F> friction force f, that is, the minimum output torque of the motor must be greater than f×V. According to the motor output power P (W) = torque (Nm) × speed (rpm) / 9550, the minimum torque of the motor that prevents the vehicle from sliding down the slope or turning over can be determined when climbing a slope.

[0103] The present invention takes into account the driving safety of the whole vehicle and its components, and is aimed at the motor torque control logic and method of new energy vehicles on bumpy roads, including but not limited to: the logic method used by the motor torque control system applicable to different models of new energy vehicles. The method of distinguishing the motor torque control when the vehicle is climbing a slope based on the determination of the bumpy road surface based on the vertical acceleration of the vehicle. The analysis method of determining the motor torque by comprehensively considering the driving safety of the whole vehicle and its components. Based on actual vehicle testing, the torque change effect and the riding experience are comprehensively considered to determine the countermeasures for the torque change rate.

[0104] Through the technology of the present invention, the motor torque control of new energy vehicles when driving on bumpy roads is realized; at the same time, the vehicle safety and the normal operation of the drive system component hardware are taken into consideration, which can reduce vehicle driving safety accidents and improve vehicle driving safety; by first determining whether the vehicle is driving on a bumpy road and establishing a motor torque control logic that distinguishes between general bumpy roads and climbing conditions, the vehicle's dynamics is improved.

[0105] A second aspect of the present invention provides an electronic device, such as Figure 7 As shown, the electronic device 100 includes: at least one processor 101 and a memory 102 .

[0106] Among them, at least one processor 101 is communicatively connected with the memory 102, and the memory 102 stores a computer program that can be executed by the at least one processor 101. When the at least one processor 101 executes the computer program, the motor torque control method is implemented.

[0107] According to the electronic device of the embodiment of the present invention, the corresponding motor torque control program can be stored in the memory. When implementing the charging control method, the processor runs the program in the memory to determine whether the vehicle is traveling on a bumpy road condition. When the vehicle is traveling on different bumpy roads, the range of the motor operating torque is controlled according to the motor torque limit torque, thereby preventing the vehicle motor transmission system from being subjected to a large impact torque and causing hardware damage, thereby improving the vehicle's power and safety, and avoiding the occurrence of vehicle driving safety accidents.

[0108] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements a motor torque control method when executed.

[0109] A fourth aspect of the present invention provides a vehicle, such as Figure 8 As shown, the vehicle 200 includes: a motor 201 , a plurality of sensors 202 , and a controller 203 .

[0110] Among them, multiple sensors 202 are used to detect vehicle information and road information; the controller 203 is connected to the multiple sensors 202 and the motor 201, and is used to control the motor according to the motor torque control method.

[0111] In a vehicle according to an embodiment of the present invention, multiple sensors detect vehicle information and road surface information in real time to determine whether the vehicle is traveling on bumpy roads. When the vehicle is traveling on different bumpy roads, a controller controls the range of the motor's operating torque according to the motor's torque limit torque to prevent the vehicle's motor transmission system from being subjected to large impact torque and causing hardware damage, thereby improving the vehicle's power and safety and avoiding the occurrence of vehicle driving safety accidents.

[0112] In the description of this specification, any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code including one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0113] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0114] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0115] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0116] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0117] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

[0118] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, substrates, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example.

[0119] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A motor torque control method, characterized in that: include: Make sure the vehicle is in a bumpy road condition; Obtaining a wheel speed impact value according to the wheel speed of the vehicle; When the wheel speed impact value exceeds the impact value threshold, obtaining the motor torque limit according to the wheel speed impact value or the wheel speed impact value and the road slope; The range of the motor operating torque is controlled according to the motor torque limit.

2. The motor torque control method according to claim 1, characterized in that: Obtaining the motor torque limit according to the wheel speed impact value and the road slope includes: When the road surface slope is less than a slope threshold, obtaining a motor torque limit coefficient according to the wheel speed impact value; A first motor torque limit is obtained according to the motor torque limit coefficient and the maximum allowable torque of the motor, and the first motor torque limit is used as the motor torque limit to control the range of the motor operating torque.

3. The motor torque control method according to claim 1, characterized in that: Obtaining the motor torque limit according to the wheel speed impact value and the road slope includes: When the road surface slope is greater than or equal to a slope threshold, obtaining a motor torque limit coefficient according to the wheel speed impact value, and obtaining a vehicle climbing torque lower limit value according to vehicle information and the road surface slope; The first motor torque limit is obtained according to the motor torque limit coefficient and the maximum allowable torque of the motor, the second motor torque limit is obtained according to the first motor torque limit and the lower limit of the vehicle climbing torque, and the second motor torque limit is used as the motor torque limit to control the range of the motor operating torque.

4. The motor torque control method according to claim 3, characterized in that: Obtaining a lower limit value of the vehicle climbing torque according to the vehicle information and the road slope includes: The lower limit value of the vehicle climbing torque is obtained according to the road slope, the vehicle pitch angle, the vehicle speed and the vehicle weight.

5. The motor torque control method according to any one of claims 2 to 4, characterized in that: Obtaining a motor torque limit coefficient according to the wheel speed impact value includes: A calibration mapping relationship is searched according to the wheel speed impact value to obtain the motor torque limit coefficient, wherein the calibration mapping relationship is a correspondence between the wheel speed impact value and the motor torque limit coefficient, and the wheel speed impact value is inversely correlated with the motor torque limit.

6. The motor torque control method according to any one of claims 1 to 4, characterized in that: The range of the motor operating torque is controlled according to the motor torque limit, including: The motor operating torque output is controlled at a preset motor torque change rate so that the motor operating torque is within a torque range limited by the motor torque limit.

7. The motor torque control method according to claim 1, characterized in that: The wheel speed impact value is obtained according to the wheel speed of the vehicle, including: Obtaining the wheel speed of the vehicle within a preset time period; Obtain the fitting equation of wheel speed and time; Obtaining a wheel speed estimation value according to the fitting equation; A wheel speed difference is obtained according to the wheel speed estimation value and the corresponding wheel speed actual measurement value to serve as the wheel speed impact value.

8. The motor torque control method according to claim 1, characterized in that: Determine that the vehicle is in rough road conditions, including: When the vertical acceleration of the vehicle in a direction perpendicular to the vehicle exceeds a vertical acceleration threshold, and the number of times the vertical acceleration exceeds the vertical acceleration threshold reaches a number threshold, it is determined that the vehicle is traveling on the bumpy road condition, wherein the number threshold is ≥1.

9. The motor torque control method according to claim 1, characterized in that: The motor torque control method further includes: When the wheel speed impact value is less than the impact value threshold and the duration for which the wheel speed impact value is less than the impact value threshold reaches a time threshold, the torque limiting control on the motor of the vehicle is exited, and the time threshold is ≥0.

10. An electronic device, characterized in that: include: at least one processor; a memory communicatively coupled to the at least one processor; The memory stores a computer program that can be executed by the at least one processor, and when the at least one processor executes the computer program, the motor torque control method according to any one of claims 1 to 9 is implemented.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the motor torque control method according to any one of claims 1 to 9 is implemented.

12. A vehicle, characterized in that: include: Motor; Multiple sensors for detecting vehicle information and road surface information; A controller is connected to the multiple sensors and the motor, and is used to control the motor according to the motor torque control method according to any one of claims 1-9.

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